Package: linux-image-powerpc64le
Severity: normal

Debian has traditionally built the ppc64el kernel with a 64k page size, however 
this decision comes with a number of drawbacks.  Much like arm64, the 
underlying ppc64el hardware supports either 4k or 64k page sizes, and the 
selection of which page size to use is largely application-specific.  Notably, 
Ubuntu has acknowledged this in recent months by offering both 64k and 4k 
kernel builds for their arm64 SBSA servers, with the "largemem" 64k variant 
targetted specifically at database, machine learning, etc.

Since ppc64el is the only higher-tier architecture in the archive that is built 
exclusively for 64k pages, it is unneccesarily exposed to various bugs that are 
not present on a 4k build, in addition to experiencing decreased performance in 
many common workloads (JIT-heavy applications such as node.js, Web browsing, 
etc.)

I would propose that Debian at minimum offer a separate 4k kernel image for 
ppc64el that could be installed instead of the default 64k page kernel.  Most 
appications will automatically detect the page size change and use the 4k pages 
available, and the few that do not will continue to function at essentially the 
same or slightly worse performance level as they did on the 64k page kernel.  
This change would be relatively trivial to implement, and if there is agreement 
on this direction I can put the required patches together.

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